North Korea Fires 2 Ballistic Missiles as Arms Rivalry Mounts

SEOUL — North Korea launched two ballistic missiles off its east coast on Wednesday, the country’s first ballistic missile test in six months and a violation of multiple United Nations Security Council resolutions that ban North Korea from conducting such tests.

Hours after the missiles were launched, South Korea announced that its president, Moon Jae-in, had just attended the test of the country’s first submarine-launched ballistic missile, making South Korea ​the seventh country in the world to operate S.L.B.M.s, after the United States, Russia, China, Britain, France and India.

​The missile tests by both Koreas on the same day dramatically highlighted the intensifying arms race on the Korean Peninsula as nuclear disarmament talks with Washington remained stalled. They also underscored the growing concern over regional stability, with Prime Minister Yoshihide Suga of Japan calling the North Korean missile launch “outrageous” and a threat to peace.

In its announcement, South Korea also revealed that it had successfully developed a supersonic cruise missile and a long-range air-to-land missile to be mounted on the KF-21, a South Korean supersonic fighter jet, and that it had developed a ballistic missile powerful enough to penetrate North Korea’s underground bunkers.

The North’s missile launch occurred a day after the special envoy from the United States urged the country to resume nuclear disarmament talks, saying that the United States had no “hostile” intent toward Pyongyang. Neighboring countries have also stepped up efforts to get North Korea to return to the negotiating table.

North Korea conducted its previous ballistic missile test in March and test-fired what it called newly developed long-range cruise missiles over the weekend. The United States has not imposed fresh sanctions in response to the North’s short-range ballistic missiles in recent years. When North Korea resumed testing of short-range ballistic missiles in 2019, Donald J. Trump, then the president, dismissed them for being short range.

“Rather than strengthen sanctions and military exercises, the allies have emphasized a willingness for dialogue and humanitarian cooperation,” said Leif-Eric Easley, a professor of international studies at Ewha Womans University in Seoul. “The problem with less than robust responses to North Korea’s tests is that deterrence can be eroded while Pyongyang advances its capabilities and normalizes its provocations.”

The Biden administration has said it would explore “practical” and “calibrated” diplomacy to achieve the goal of the complete denuclearization of the Korean Peninsula. North Korea has yet to respond to the invitation to dialogue.

The North Korean missiles on Wednesday — launched from Yangdok, in the central part of the country — flew 497 miles and reached an altitude of 37 miles before landing in the sea between North Korea and Japan, the South Korean military said. South Korean and United States defense officials were analyzing the data collected from the test to determine exactly what type of ballistic missiles were used, it said.

Japan’s Ministry of Defense issued a statement saying…